What is a primary effect of estrogen in the female body?

Estrogen plays a crucial role in the regulation of the menstrual cycle, which is its primary effect in the female body. It helps to prepare the uterine lining for potential implantation and coordinates the complex interplay of hormones that govern the cycle. Estrogen is involved in the proliferation of the endometrial lining and the maintenance of various reproductive tissues during the menstrual phases.

Additionally, through its influence on the hypothalamic-pituitary-gonadal axis, estrogen helps to regulate not only the menstrual cycle but also the timing of ovulation. Proper regulation of the cycle is essential for fertility and overall reproductive health. This regulatory role highlights estrogen's significance in female reproductive physiology.

Other options, such as the development of male secondary sex characteristics, stimulation of cortisol production, and inhibition of thyroid hormone release, do not accurately reflect estrogen's primary functions in the female body. These alternatives either pertain to functions unrelated to estrogen or describe effects primarily associated with other hormones.